The state’s IOUs are on track for 50% renewables by 2020, but the goal is 100% clean energy by 2045 and there are still unanswered questions on how to reach it.

The path to 100% emissions-free energy by 2045 in California is not completely carved, and answers are still forthcoming.

Most of the state’s load serving entities (LSEs) required to meet the SB 100 mandate of 60% renewables by 2030 have met their 2017 interim requirement of 27%, according to the California Public Utilities Commission’s (CPUC) latest annual RPS report. California’s three dominant investor-owned utilities (IOUs) have reached 33% renewables and are on track for 50% by 2020.

But reaching the 2045 zero emissions goal — also part of SB 100 — will require a wide range of changes, including reducing reliance on natural gas in the power sector and on gasoline-fueled vehicles in the transportation sector.

California’s grid operator has not taken on the 100% emissions-free goal yet because the CPUC’s integrated resource planning (IRP) process “has not reviewed the implementation of SB 100,” California Independent System Operator (CAISO) spokesperson Anne Gonzales told Utility Dive. A “preferred system plan” is expected some time in the first quarter of 2019.

The CPUC’s IRP process has not addressed technical needs for 60% renewables, but has studied “amounts near 57%, which gets us close,” Gonzales said. CAISO has an eight-solution menu for meeting the “current and future renewable energy goals” that includes more distributed energy resources (DER) and demand response, time-of-use rates, transportation electrification and a regional grid.